Many image forming devices, e.g., copiers, printers, plotters, etc., include a controlling microprocessor which stores calibration data that enable adjustment of internal components in such a manner as to assure high quality document production. The calibration data is generally configured in the form of control parameters which are stored in either a random access memory or read-only memory, as the case may be. The prior art teaches that such parameters can be stored directly on memory chips that are resident on replaceable consumable devices utilized with such devices.
In laser based printers, the electrophotographic process relies on control of toner particles and charge states. These fundamental materials and forces are influenced by a variety of external and internal conditions experienced in the printing process. Humidity, temperature, contaminants found on the surface of the photoreceptor, conditioning of the photoreceptor by previously printed patterns, manufacturing variations, etc. all affect the quality of printed image. Most electrophotographic processes incorporated into laser printers select specific operating conditions which are then held constant. At times, such operating conditions may be adjusted in accordance with temperature and/or humidity conditions. Nevertheless, the conditions are set so as to try to achieve acceptable printed images under most of the potential conditions which may be experienced by the printer.
U.S. Pat. No. 4,961,088 to Gilliland et al. describes a toner cartridge which includes a programmable read-only memory that is programmed with a cartridge identification number. That cartridge identification number, when matched with a cartridge identification number stored in a printer that receives the cartridge, enables further printer operations. The read-only memory on the cartridge also includes a cartridge replacement warning count and a termination count at which the cartridge is disabled from further use. The read-only memory on the cartridge further stores updated counts of the remaining number of images left on the cartridge, after each print run.
U.S. Pat. No. 5,049,898 to Arthur et al., assigned to the same Assignee as this Application, discloses a disposable printing assembly wherein an integral memory element stores data that characterizes the assembly. Arthur et al. provide an inkjet printhead assembly with a memory which designates the color of the ink in the printhead, its amount and the position of the inkjet orifice plate on the printhead body. This data is read from the printhead by a read/write element in the printer and is then used or displayed, as desired.
U.S. Pat. No. 5,491,540 to Hirst, assigned to the same Assignee as this application, describes a printer/copier apparatus wherein a disposable part of the apparatus includes a memory chip with control parameters relating to the consumable. Data transfers are enabled both to and from the memory chip via a serial access line (which replaces a previously used fuse connection).
U.S. Pat. Nos. 5,138,344 to Ujita; 5,365,312 to Hillmann et al.; and 5,610,635 to Murray et al. all relate to and describe various aspects of memory storage elements that are incorporated on ink cartridges used with inkjet printers. In each case, the memory storage element includes data related to the consumption of ink from the ink cartridge; the ink color and other data relating to the consumable.
U.S. Pat. No. 5,235,384 to Oka et al. describes a print apparatus wherein a user's selection of a print mode enables control conditions to be read from a memory included on a consumable item that is incorporated into the printer. Those parameters are then used to set up the printer in accordance with the desired mode.
Notwithstanding that various control parameters are taught as being stored on memory chips resident on consumable items, use of such parameters (and their updates) is generally based upon projected changes in print image characteristics which result from alterations of the state of the consumable items. Such alterations are those which are predicted by the manufacturer, but which may not be entirely accurate due to the wide variety of changes which can occur in the print mechanism and consumable items.
Accordingly, it is an object of this invention to provide a method and apparatus for adaptively controlling a printer which is subject to changed print conditions.
It is another object of this invention to provide an improved adaptive printer control method and apparatus wherein altered control conditions are achieved through examination of actually produced images.